As various control targets have been electronically controlled, electric actuators such as an injector, an igniter, a motor, a solenoid, and a relay have been widely used. As disclosed in Patent Literature 1, for example, an electronic control device for controlling these actuators generally includes two kinds of ICs: one is a driving IC that drives the actuators (loads), and the other is a control IC that generates pulses for driving the loads.
In recent years, along with the advance of performance of the electronic control devices, it has become possible for one driving IC to drive many loads. In this case, there arises a problem in that, because the number of signals transmitted between the driving IC and the control IC increases, it becomes necessary that a package with a large number of pins should be employed for each IC and the wiring area of board for mounting each IC should be wide, with the result that the cost and size of the electronic control device increase. In order to address this problem, measures to reduce the number of signals transmitted between the driving IC and the control IC are taken using the micro second bus (MSB) that is a communication protocol used for serially transmitting plural pulse signals between the driving IC and the control IC.